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Solving a Software RAID Problem with Diskpart

Question

There is a Windows 2008 Server with two disks having a Software RIAD. One of the disks is marked as "missing". I try to reactivate the missing disk with the help of Disk Management. Immediately the message "The Plex is missing" is given (translated from
German). I read about replacing a failed disk in
http://technet.microsoft.com/en-us/library/cc758037(WS.10).aspx. However, not being an administrator at all, I am somewhat unsure.

At the end of this thread there is some information from diskpart. By reading the above article, I understand...

There are two disks, named "0" and "M0".

The disk "M0" is marked as missing ("fehlend" in German).

I would separate the disks with...

break disk M0 nokeep

Then I would select a volume and add the previously missing disk...

select volume 0

add disk M0

Do I have to do this for both volumes (partitions C and D)? Does adding a disk always mirror a complete disk? Or do I have to also execute?

select volume 1

add disk M0

When will the previously missing disk be formatted? When "add disk M0" is executed? If so, is it ok to execute it twice (once for C and D)?

Answers

From the OP, you have 2 disks which are mirrored. The mirrored disks (RAID1) are partitioned as Volume0 and Volume12. The Volume0 (c:) is a system volume.

Above all you will need to confirm if the M0 disk is actually broken or not. If it is broken/corrupted, as you said, now you need to remove the corrupted disk (M0) and replace it with a health one. And both volumes need to be mirrored manually with commands
"select + add".

As the volume0 is a system volume, you may need to perform the steps in following article to create a mirrored system volume:

All replies

From the OP, you have 2 disks which are mirrored. The mirrored disks (RAID1) are partitioned as Volume0 and Volume12. The Volume0 (c:) is a system volume.

Above all you will need to confirm if the M0 disk is actually broken or not. If it is broken/corrupted, as you said, now you need to remove the corrupted disk (M0) and replace it with a health one. And both volumes need to be mirrored manually with commands
"select + add".

As the volume0 is a system volume, you may need to perform the steps in following article to create a mirrored system volume:

I have successfully separated the mirror with the help of DISKPART. There were no problems. A new disk will be built into the server soon.

I had to use DISKPART, as Disk Management did not offer the commands for separating the disk, or for reactivating the second disk. They were grayed out. If the new disk is inside the server, I will then use Disk Management.

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